@inproceedings{Toppan:20042d, author = "Toppan, Francesco", title = "{On a Division Algebra Classification of Constrained}", doi = "10.22323/1.013.0047", booktitle = "Proceedings of Fourth International Winter Conference on Mathematical Methods in Physics {\textemdash} PoS(WC2004)", year = 2004, volume = "013", pages = "047" }